#ifndef MULTIBOOT_HEADER
#define MULTIBOOT_HEADER 1

/*
 * from multiboot.h, source:
 * https://www.gnu.org/software/grub/manual/multiboot/multiboot.html
 */

/*-
 * Copyright (C) 1999,2003,2007,2008,2009  Free Software Foundation, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL ANY
 * DEVELOPER OR DISTRIBUTOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
 * IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
     
/* How many bytes from the start of the file we search for the header. */
#define MULTIBOOT_SEARCH		8192
     
#define MULTIBOOT_HEADER_MAGIC		0x1badb002
#define MULTIBOOT_BOOTLOADER_MAGIC	0x2badb002
#define MULTIBOOT_UNSUPPORTED		0x0000fffc
#define MULTIBOOT_MOD_ALIGN		0x00001000
#define MULTIBOOT_INFO_ALIGN		0x00000004
     
/*
 * Flags set in the 'flags' member of the multiboot header.
 */
     
#define MULTIBOOT_PAGE_ALIGN                    0x00000001
#define MULTIBOOT_MEMORY_INFO                   0x00000002
#define MULTIBOOT_VIDEO_MODE                    0x00000004
#define MULTIBOOT_AOUT_KLUDGE                   0x00010000
     
/*
 * Flags to be set in the 'flags' member of the multiboot info structure.
 */
     
#define MULTIBOOT_INFO_MEMORY		0x00000001
#define MULTIBOOT_INFO_BOOTDEV		0x00000002
#define MULTIBOOT_INFO_CMDLINE		0x00000004
#define MULTIBOOT_INFO_MODS		0x00000008
#define MULTIBOOT_INFO_AOUT_SYMS	0x00000010
#define MULTIBOOT_INFO_ELF_SHDR		0x00000020
#define MULTIBOOT_INFO_MEM_MAP		0x00000040
#define MULTIBOOT_INFO_DRIVE_INFO	0x00000080
#define MULTIBOOT_INFO_CONFIG_TABLE 	0x00000100
#define MULTIBOOT_INFO_BOOT_LOADER_NAME	0x00000200
#define MULTIBOOT_INFO_APM_TABLE	0x00000400
#define MULTIBOOT_INFO_VIDEO_INFO	0x00000800

#ifndef _LOCORE

typedef unsigned short          multiboot_uint16_t;
typedef unsigned int            multiboot_uint32_t;
typedef unsigned long long      multiboot_uint64_t;

struct multiboot_header {
	/* Must be MULTIBOOT_MAGIC - see above. */
	multiboot_uint32_t magic;

	/* Feature flags. */
	multiboot_uint32_t flags;

	/* The above fields plus this one must equal 0 mod 2^32. */
	multiboot_uint32_t checksum;

	/* These are only valid if MULTIBOOT_AOUT_KLUDGE is set. */
	multiboot_uint32_t header_addr;
	multiboot_uint32_t load_addr;
	multiboot_uint32_t load_end_addr;
	multiboot_uint32_t bss_end_addr;
	multiboot_uint32_t entry_addr;

	/* These are only valid if MULTIBOOT_VIDEO_MODE is set. */
	multiboot_uint32_t mode_type;
	multiboot_uint32_t width;
	multiboot_uint32_t height;
	multiboot_uint32_t depth;
};

/* The symbol table for a.out. */
struct multiboot_aout_symbol_table {
	multiboot_uint32_t tabsize;
	multiboot_uint32_t strsize;
	multiboot_uint32_t addr;
	multiboot_uint32_t reserved;
};

/* The section header table for ELF. */
struct multiboot_elf_section_header_table {
	multiboot_uint32_t num;
	multiboot_uint32_t size;
	multiboot_uint32_t addr;
	multiboot_uint32_t shndx;
};

struct multiboot_info {
	/* Multiboot info version number */
	multiboot_uint32_t flags;

	/* Available memory from BIOS */
	multiboot_uint32_t mem_lower;
	multiboot_uint32_t mem_upper;

	/* "root" partition */
	multiboot_uint32_t boot_device;

	/* Kernel command line */
	multiboot_uint32_t cmdline;

	/* Boot-Module list */
	multiboot_uint32_t mods_count;
	multiboot_uint32_t mods_addr;

	union {
		struct multiboot_aout_symbol_table aout_sym;
		struct multiboot_elf_section_header_table elf_sec;
	} u;

	/* Memory Mapping buffer */
	multiboot_uint32_t mmap_length;
	multiboot_uint32_t mmap_addr;

	/* Drive Info buffer */
	multiboot_uint32_t drives_length;
	multiboot_uint32_t drives_addr;

	/* ROM configuration table */
	multiboot_uint32_t config_table;

	/* Boot Loader Name */
	multiboot_uint32_t boot_loader_name;

	/* APM table */
	multiboot_uint32_t apm_table;

	/* Video */
	multiboot_uint32_t vbe_control_info;
	multiboot_uint32_t vbe_mode_info;
	multiboot_uint16_t vbe_mode;
	multiboot_uint16_t vbe_interface_seg;
	multiboot_uint16_t vbe_interface_off;
	multiboot_uint16_t vbe_interface_len;
};
     
struct multiboot_mmap_entry {
	multiboot_uint32_t size;
	multiboot_uint64_t addr;
	multiboot_uint64_t len;
#define MULTIBOOT_MEMORY_AVAILABLE              1
#define MULTIBOOT_MEMORY_RESERVED               2
	multiboot_uint32_t type;
} __attribute__((packed));
     
struct multiboot_mod_list {
	/* the memory goes from bytes 'mod_start' to 'mod_end-1' inclusive */
	multiboot_uint32_t mod_start;
	multiboot_uint32_t mod_end;

	/* Module command line */
	multiboot_uint32_t cmdline;

	/* padding to take it to 16 bytes (must be zero) */
	multiboot_uint32_t pad;
};

#endif /* ! _LOCORE */
#endif /* ! MULTIBOOT_HEADER */
